Introduction: Almost half of neonates with congenital heart disease (CHD) require heart surgery during their 1st month of life, which exposes them to an increased risk of brain injury. It is necessary to find effective neuroprotective strategies to improve their neurological outcome. Dexmedetomidine (Dex) has demonstrated potential neuroprotective effects in several animal studies. Ketamine remains controversial regarding its effects on the brain. Our objective is to evaluate the effect of intraoperative administration of Dex and/or Ketamine on postoperative EEG evolution.
Methods: We included a cohort of 44 neonates (29 boys) with CHD that underwent cardiac surgery at <44 weeks postmenstrual age. Medical records were reviewed to collect clinical data. Preoperative and postoperative EEG recordings (from 15 to 24h postoperatively), were submitted to quantitative analysis to derive EEG discontinuity. Statistical analyses were done (Analyses of variance for repeated measures adjusted with duration of anesthesia and postmenstrual age (PMA) at surgery, 2-way ANOVA and Spearman correlations).
Results: We found a significant effect of the combination of Dex and Ketamine on the evolution of postoperative EEG (F(1,29)=5.38, p=0.028). More specifically, this interaction was only significant at 18 hours after surgery (F(1,38)=4.70, p=0.037). Simple effects showed that the combination had a significantly higher postoperative discontinuity in comparison with the groups Dex (F(1,36)=7.34, p=0.010) and Ketamine (F(1,36)=7.11, p=0.011). Also, we found a trend of a better EEG recovery at 24 hours postoperative following higher doses of Ketamine administered during surgery (p=0.085, r=-0.28).
Conclusion: Intraoperative administration of Dex alone and Ketamine alone is associated with a better recovery of the brain activity 18 hours after surgery in comparison with the group who had a combination of Dex and Keta and a trend for the control group. Finally, higher doses of ketamine would lead to a better recovery of activity at 24 hours after surgery.
Béatrice Desnous– Fellow neurologist, CHU Sainte Justine
Bohdana Marandyuk– Research associates, CHU Sainte Justine
kim anh La– Medical student, CHU Sainte Justine
Lixin Zhang– Medical student, CHU Sainte Justine
Geneviève Côté– Anesthesiologist, CHU Sainte Justine
Elana Pinchefsky– Neurologist, CHU Sainte Justine